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large beardtongue, largeflower penstemon, shell-leaf beardtongue

low beardtongue, lowly penstemon

Habit Herbs.
Stems

erect, (40–)50–95(–120) cm, glabrous.

decumbent to erect, (2–)5–30(–65) cm, retrorsely hairy, not glaucous.

Leaves

basal and cauline, glabrous;

basal and proximal cauline 30–160 × 6–50 mm, blade spatulate to obovate, base tapered, apex rounded to obtuse or acute;

cauline 4–8 pairs, sessile, 18–90(–110) × 15–50 mm, blade spatulate to orbiculate, base clasping, apex rounded to obtuse.

basal and cauline, not leathery, glabrous or retrorsely hairy;

basal and proximal cauline (8–)15–105 × 2–22(–32) mm, blade obovate to ovate or oblanceolate, base tapered, margins entire, sometimes serrulate or serrate, apex obtuse to acute;

cauline (1 or)2–4 pairs, sessile or proximals short-petiolate, 10–35(–45) × 1–11 mm, blade obovate to oblanceolate or lanceolate, base tapered to clasping, margins entire, rarely ± serrate, apex obtuse to acute.

Thyrses

interrupted, cylindric, 12–30(–40) cm, axis glabrous, verticillasters 3–7(–9), cymes 2–4-flowered;

proximal bracts ovate to elliptic or orbiculate, (9–)16–83 × (9–)16–54 mm;

peduncles and pedicels glabrous.

interrupted, cylindric to ± secund, (1–)3–20(–39) cm, axis moderately glandular-pubescent, verticillasters (1–)3–9(–11), cymes (1 or)2–6(–11)-flowered, 2 per node;

proximal bracts lanceolate, rarely ovate, 6–34(–48) × 1–11 mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent and, usually, retrorsely hairy.

Flowers

calyx lobes ovate to lanceolate, 7–11 × 2.5–4 mm, margins entire, rarely erose, herbaceous or narrowly scarious, glabrous;

corolla lavender to blue or pinkish blue, with magenta nectar guides, ampliate, 35–48 mm, glabrous externally, glabrous internally, tube 10–13 mm, throat abruptly inflated, 15–18 mm diam., rounded abaxially;

stamens included, pollen sacs opposite, 2.1–2.6 mm, sutures papillate;

staminode 16–21 mm, included or reaching orifice, 2–2.6 mm diam., tip recurved to coiled, distal 1–2 mm sparsely villous, hairs golden yellow, to 0.5 mm;

style 19–30 mm.

calyx lobes ovate to lanceolate, 2.8–5(–6) × 1–1.9 mm, margins entire or erose, apex acute, glandular-pubescent;

corolla blue to purple or violet, with reddish violet nectar guides, bilabiate, not personate, tubular-funnelform, (7–)8–19 mm, glandular-pubescent externally, sparsely to moderately white- or yellow-lanate internally abaxially, tube 2–5 mm, throat slightly inflated, (3–)4.5–6 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, 0.5–0.8 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth or papillate;

staminode (3–)7–9 mm, included, 0.1–0.3 mm diam., tip slightly recurved, distal 1–4 mm sparsely to densely pilose, hairs yellow or golden yellow, to 0.7 mm (medial hairs sparser and shorter);

style 6–12 mm.

Capsules

16–20(–25) × 8–15 mm.

4–6 × 2.5–3.5 mm, glabrous.

2n

= 16.

Penstemon grandiflorus

Penstemon humilis

Phenology Flowering Apr–Jul.
Habitat Sandy or calcareous soils, tallgrass, mixed-grass, and sand prairies.
Elevation 200–1800(–2400) m. (700–5900(–7900) ft.)
Distribution
from FNA
CO; CT; IA; IL; IN; KS; MA; MI; MN; MO; MT; ND; NE; NM; OH; OK; SD; TX; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Widely distributed in the western Midwest and Great Plains in the United States, Penstemon grandiflorus is cultivated as an ornamental for its showy flowers. Reports from Connecticut (D. W. Magee and H. E. Ahles 2007), Indiana (K. Yatskievych 2000), Massachusetts (Magee and Ahles), Michigan (E. G. Voss 1972–1996), and Ohio (T. S. Cooperrider 1995) appear to be based on introductions. Penstemon grandiflorus has been seeded along highways in Iowa and Nebraska, where it is also native.

The validity of the name Penstemon grandiflorus has been debated owing to the meager diagnosis by Nuttall. The name is accepted here, making P. bradburyi Pursh, an illegitimate, superfluous replacement for P. grandiflorus.

The Dakota, Kiowa, and Sioux tribes, centered in the Great Plains, use Penstemon grandiflorus as an analgesic, a gastrointestinal aid, and for fevers (D. E. Moerman 1998).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 3 (3 in the flora).

Penstemon humilis is widespread and extremely variable throughout its range in the western United States. Except for two fairly distinct elements in Utah, most variation in the species is contained in the widespread var. humilis. D. D. Keck (1945) and N. H. Holmgren (1984) summarized the ranges and morphologic tendencies of some of the more distinctive phases.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Cauline leaf blade margins ± serrate; basal leaves (4–)7–22(–32) mm wide; sw Utah.
var. obtusifolius
1. Cauline leaf blade margins entire, rarely ± serrate distally; basal leaves 2–20 mm wide; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming.
→ 2
2. Basal leaves puberulent or retrorsely hairy; corollas (7–)12–19 mm; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming.
var. humilis
2. Basal leaves glabrous, sometimes ± puberulent, especially along midveins and margins; corollas 10–13 mm; nc Utah.
var. brevifolius
Source FNA vol. 17, p. 118. FNA vol. 17, p. 208.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon
Sibling taxa
P. abietinus, P. absarokensis, P. acaulis, P. acuminatus, P. alamosensis, P. albertinus, P. albidus, P. albomarginatus, P. ambiguus, P. ammophilus, P. anguineus, P. angustifolius, P. arenarius, P. arenicola, P. aridus, P. arkansanus, P. attenuatus, P. atwoodii, P. auriberbis, P. australis, P. azureus, P. baccharifolius, P. barbatus, P. barnebyi, P. barrettiae, P. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, P. caespitosus, P. calcareus, P. californicus, P. calycosus, P. canescens, P. cardinalis, P. cardwellii, P. carnosus, P. caryi, P. centranthifolius, P. cinicola, P. clevelandii, P. clutei, P. cobaea, P. comarrhenus, P. compactus, P. concinnus, P. confertus, P. confusus, P. crandallii, P. cusickii, P. cyananthus, P. cyaneus, P. cyanocaulis, P. cyathophorus, P. dasyphyllus, P. davidsonii, P. deamii, P. deaveri, P. debilis, P. degeneri, P. deustus, P. digitalis, P. diphyllus, P. discolor, P. dissectus, P. distans, P. dolius, P. duchesnensis, P. eatonii, P. elegantulus, P. ellipticus, P. eriantherus, P. euglaucus, P. fendleri, P. filiformis, P. flavescens, P. floribundus, P. floridus, P. flowersii, P. franklinii, P. fremontii, P. fruticiformis, P. fruticosus, P. gairdneri, P. gibbensii, P. glaber, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. gracilis, P. grahamii, P. griffinii, P. grinnellii, P. guadalupensis, P. hallii, P. harbourii, P. harringtonii, P. havardii, P. haydenii, P. heterodoxus, P. heterophyllus, P. hirsutus, P. humilis, P. idahoensis, P. immanifestus, P. incertus, P. inflatus, P. jamesii, P. janishiae, P. kingii, P. kralii, P. labrosus, P. laetus, P. laevigatus, P. laevis, P. lanceolatus, P. laricifolius, P. laxiflorus, P. laxus, P. leiophyllus, P. lemhiensis, P. lentus, P. leonardii, P. linarioides, P. longiflorus, P. lyallii, P. marcusii, P. mensarum, P. metcalfei, P. miser, P. moffatii, P. monoensis, P. montanus, P. moriahensis, P. mucronatus, P. multiflorus, P. murrayanus, P. nanus, P. navajoa, P. neomexicanus, P. neotericus, P. newberryi, P. nitidus, P. nudiflorus, P. oklahomensis, P. oliganthus, P. ophianthus, P. osterhoutii, P. ovatus, P. pachyphyllus, P. pahutensis, P. pallidus, P. palmeri, P. papillatus, P. parryi, P. parvulus, P. parvus, P. patens, P. payettensis, P. paysoniorum, P. peckii, P. penlandii, P. pennellianus, P. perpulcher, P. personatus, P. petiolatus, P. pinifolius, P. pinorum, P. platyphyllus, P. pratensis, P. procerus, P. pruinosus, P. pseudoputus, P. pseudospectabilis, P. pudicus, P. pumilus, P. purpusii, P. putus, P. radicosus, P. rattanii, P. retrorsus, P. rhizomatosus, P. richardsonii, P. roezlii, P. rostriflorus, P. rubicundus, P. rupicola, P. rydbergii, P. saxosorum, P. scapoides, P. scariosus, P. secundiflorus, P. seorsus, P. sepalulus, P. serrulatus, P. smallii, P. spatulatus, P. speciosus, P. spectabilis, P. stenophyllus, P. stephensii, P. strictiformis, P. strictus, P. subglaber, P. subserratus, P. subulatus, P. sudans, P. superbus, P. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tiehmii, P. tracyi, P. triflorus, P. triphyllus, P. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
P. abietinus, P. absarokensis, P. acaulis, P. acuminatus, P. alamosensis, P. albertinus, P. albidus, P. albomarginatus, P. ambiguus, P. ammophilus, P. anguineus, P. angustifolius, P. arenarius, P. arenicola, P. aridus, P. arkansanus, P. attenuatus, P. atwoodii, P. auriberbis, P. australis, P. azureus, P. baccharifolius, P. barbatus, P. barnebyi, P. barrettiae, P. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, P. caespitosus, P. calcareus, P. californicus, P. calycosus, P. canescens, P. cardinalis, P. cardwellii, P. carnosus, P. caryi, P. centranthifolius, P. cinicola, P. clevelandii, P. clutei, P. cobaea, P. comarrhenus, P. compactus, P. concinnus, P. confertus, P. confusus, P. crandallii, P. cusickii, P. cyananthus, P. cyaneus, P. cyanocaulis, P. cyathophorus, P. dasyphyllus, P. davidsonii, P. deamii, P. deaveri, P. debilis, P. degeneri, P. deustus, P. digitalis, P. diphyllus, P. discolor, P. dissectus, P. distans, P. dolius, P. duchesnensis, P. eatonii, P. elegantulus, P. ellipticus, P. eriantherus, P. euglaucus, P. fendleri, P. filiformis, P. flavescens, P. floribundus, P. floridus, P. flowersii, P. franklinii, P. fremontii, P. fruticiformis, P. fruticosus, P. gairdneri, P. gibbensii, P. glaber, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. gracilis, P. grahamii, P. grandiflorus, P. griffinii, P. grinnellii, P. guadalupensis, P. hallii, P. harbourii, P. harringtonii, P. havardii, P. haydenii, P. heterodoxus, P. heterophyllus, P. hirsutus, P. idahoensis, P. immanifestus, P. incertus, P. inflatus, P. jamesii, P. janishiae, P. kingii, P. kralii, P. labrosus, P. laetus, P. laevigatus, P. laevis, P. lanceolatus, P. laricifolius, P. laxiflorus, P. laxus, P. leiophyllus, P. lemhiensis, P. lentus, P. leonardii, P. linarioides, P. longiflorus, P. lyallii, P. marcusii, P. mensarum, P. metcalfei, P. miser, P. moffatii, P. monoensis, P. montanus, P. moriahensis, P. mucronatus, P. multiflorus, P. murrayanus, P. nanus, P. navajoa, P. neomexicanus, P. neotericus, P. newberryi, P. nitidus, P. nudiflorus, P. oklahomensis, P. oliganthus, P. ophianthus, P. osterhoutii, P. ovatus, P. pachyphyllus, P. pahutensis, P. pallidus, P. palmeri, P. papillatus, P. parryi, P. parvulus, P. parvus, P. patens, P. payettensis, P. paysoniorum, P. peckii, P. penlandii, P. pennellianus, P. perpulcher, P. personatus, P. petiolatus, P. pinifolius, P. pinorum, P. platyphyllus, P. pratensis, P. procerus, P. pruinosus, P. pseudoputus, P. pseudospectabilis, P. pudicus, P. pumilus, P. purpusii, P. putus, P. radicosus, P. rattanii, P. retrorsus, P. rhizomatosus, P. richardsonii, P. roezlii, P. rostriflorus, P. rubicundus, P. rupicola, P. rydbergii, P. saxosorum, P. scapoides, P. scariosus, P. secundiflorus, P. seorsus, P. sepalulus, P. serrulatus, P. smallii, P. spatulatus, P. speciosus, P. spectabilis, P. stenophyllus, P. stephensii, P. strictiformis, P. strictus, P. subglaber, P. subserratus, P. subulatus, P. sudans, P. superbus, P. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tiehmii, P. tracyi, P. triflorus, P. triphyllus, P. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Subordinate taxa
P. humilis var. brevifolius, P. humilis var. humilis, P. humilis var. obtusifolius
Name authority Nuttall: Cat. Pl. Upper Louisiana, no. 64. (1813) — (as grandiflorum) Nuttall ex A. Gray: Proc. Amer. Acad. Arts 6: 69. (1862) — (as Pentstemon)
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